1. Field of the Invention
The present invention relates to an image display, and more particularly, it relates to an image display providing stereoscopic images etc. to observers.
2.Cross-Reference to Related Applications
The priority application No. JP2005-76195 upon which this patent application is based is hereby incorporated by reference.
3. Description of the Background Art
For example, Japanese Patent Laying-Open No. 10-161061 (1998) discloses a stereoscopic image display displaying three-dimensional stereoscopic images.
As shown in FIG. 18, the stereoscopic image display 500 disclosed in Japanese Patent Laying-Open No. 10-161061 comprises a backlight 501, a liquid crystal panel 502, arranged on a light emission side of the backlight 501, having shielding portions 502a and translucent portions 502b, polarizing plates 503 and 504 opposed to each other to hold the liquid crystal panel 502 therebetween, a lenticular lens 505, provided separately from the liquid crystal panel 502, arranged on a light emission side of the polarizing plate 504 and an image display liquid crystal panel 506 arranged on a light emission side of the lenticular lens 505 for displaying images. The liquid crystal panel 502 is provided with a plurality of vertically striped transparent conductive films formed on a transparent substrate. The shielding portions 502a and the translucent portions 502b of the aforementioned liquid crystal panel 502 are provided in correspondence to the transparent conductive films. In other words, the shielding portions 502a and the translucent portions 502b are provided in one-to-one correspondence to the vertically striped transparent conductive films of the liquid crystal panel 502 respectively in the stereoscopic image display 500 disclosed in Japanese Patent Laying-Open No. 10-161061. The lenticular lens 505 condenses light irradiated from the backlight 501 and transmitted through the translucent portions 502b provided in correspondence to the transparent conductive films on a light arrival area 520 having a length X in a direction A shown in FIG. 18 on a position where an observer 510 is located.
The stereoscopic image display 500 disclosed in Japanese Patent Laying-Open No. 10-161061 alternately displays left- and right-eye images on the image display liquid crystal panel 506 and switches the shielding portions 502a and the translucent portions 502b of the liquid crystal panel 502 by controlling application of voltage to the transparent conductive films in synchronization with the switching of the display. Thus, the stereoscopic image display 500 guides only the right-eye images to the right eye 510a of the observer 510 while the image display liquid crystal panel 506 displays the right-eye images, and guides only the left-eye images to the left eye 510b of the observer 510 while the image display liquid crystal panel 506 displays the left-eye images. The stereoscopic image display 500 repeats this switching operation, so that the observer 510 can observe stereoscopic images.
In the stereoscopic image display 500 disclosed in Japanese Patent Laying-Open No. 10-161061 having the shielding portions 502a and the translucent portions 502b of the liquid crystal panel 502 in one-to-one correspondence to the transparent conductive films provided on the transparent substrate of the liquid crystal panel 502, however, it is difficult to arbitrary change the length of the shielding portions 502a and the translucent portions 502b in the direction A shown in FIG. 18. Thus, it is difficult to subdivide or enlarge sets of the shielding portions 502a and the translucent portions 502b of the same liquid crystal panel 502, and hence it is disadvantageously difficult to reduce or increase the length X of the light arrival area 520 formed by the light passing through the translucent portions 502b of the same liquid crystal panel 502 in the direction A. Therefore, it is disadvantageously difficult to provide stereoscopic images to a plurality of observers by reducing the length X of the light arrival area 520 in the direction A shown in FIG. 18 thereby individually introducing light into the left and right eyes of the plurality of observers or to provide different planar images (two-dimensional images) to a plurality of observers located on different observational positions respectively by increasing the length X of the light arrival area 520 in the direction A shown in FIG. 18 through the same liquid crystal panel (light emission control means) 502.